23 May 2007

Radiation-eating Fungi

Science Daily — Scientists have long assumed that fungi exist mainly to decompose matter into chemicals that other organisms can then use. But researchers at the Albert Einstein College of Medicine of Yeshiva University have found evidence that fungi possess a previously undiscovered talent with profound implications: the ability to use radioactivity as an energy source for making food and spurring their growth.

Those fungi able to "eat" radiation must possess melanin, the pigment found in many if not most fungal species. But up until now, melanin's biological role in fungi--if any--has been a mystery.

"Just as the pigment chlorophyll converts sunlight into chemical energy that allows green plants to live and grow, our research suggests that melanin can use a different portion of the electromagnetic spectrum--ionizing radiation--to benefit the fungi containing it," says Dr. Dadachova.....The research began five years ago when Dr. Casadevall read on the Web that a robot sent into the still-highly-radioactive damaged reactor at Chernobyl had returned with samples of black, melanin-rich fungi that were growing on the reactor's walls. "I found that very interesting and began discussing with colleagues whether these fungi might be using the radiation emissions as an energy source," says Dr. Casadevall.....Dr. Casadevall notes that the melanin in fungi is no different chemically from the melanin in our skin. "It's pure speculation but not outside the realm of possibility that melanin could be providing energy to skin cells," he says. "While it wouldn't be enough energy to fuel a run on the beach, maybe it could help you to open an eyelid."